The walking male: activity, climate influence and locomotor performance in the male movement of an endangered tarantula (Grammostola vachoni) over the reproductive season

SCHWERDT, LEONELA; FERRETTI, NELSON; COPPERI, SOFÍA; POMPOZZI, GABRIEL

BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2022

0024-4066

In tarantulas the reproductive season is highlighted by the presence of walking males in their natural habitat. Grammostola vachoni is a tarantula from Argentine, and previous studies have reported the breeding season to occur only in spring; however, walking males also are observed in other months. Thus, our objectives were to study the dynamics of G. vachoni in the reproductive season; to compare male activity with climate data; and to estimate if temperature affects male locomotor performance. Two peaks of walking male activity were reported (from the end of October to December, and in March). The number of walking females registered was low and showed a bimodal occurrence. No significant differences between sexes in activity temperature and atmospheric pressure were observed, but the observations of females occurred under the highest humidity conditions. The reproductive season months were very similar in their climate characteristics. Male locomotor performance was strongly affected by extreme temperatures, and the optimum experimental temperature was higher than environmental activity temperature. This study suggests a diplochronous cycle for G. vachoni, which might be a historical constraint or might be indicating pressure selection over any of the peaks.